The HIROSHIMA Study: A High-Volume, Institutional, Retrospective, Observational Study of Hidden Non-Incisional Suture Double Eyelid Surgery for Multivariate Analysis of Crease Loss.

[BACKGROUND] Non-incisional double eyelid surgery is widely performed in East Asia, but crease loss remains a major concern, leading to patient dissatisfaction and revision. The relative impact of surgical technique, anatomical characteristics, and surgeon experience on crease retention has not been fully clarified.

[METHODS] This retrospective, observational study included 513 consecutive patients who underwent transcutaneous, non-incisional double eyelid surgery between July 2021 and July 2022. Patients were stratified by surgeon experience (<100 vs. ≥100 prior cases). Baseline variables included age, sex, crease design, fixation method, puffy eyelid status, and surgeon experience. Crease loss was defined as the need for revision due to patient-reported fading or disappearance of the crease. Kaplan-Meier analysis and Cox proportional hazards regression were used to evaluate predictors of crease survival, including interaction terms for potential effect modification.

[RESULTS] Of 513 patients, 264 were treated by beginner surgeons, and 249 by experienced surgeons. Experienced surgeons more frequently used the continuous buried suture method (  < 0.001), whereas baseline characteristics such as age, sex, and crease design were comparable between groups. Overall prevalence of puffy eyelids was 54.5%, with substantial interrater agreement (κ = 0.72). Kaplan-Meier analysis demonstrated significantly superior outcomes with continuous fixation compared to interrupted fixation (log-rank  < 0.001), and with non-puffy compared to puffy eyelids (log-rank  < 0.001). Surgeon experience showed no significant effect (  = 0.441). In multivariable Cox regression, continuous fixation (HR = 0.29, 95% CI 0.19-0.44,  < 0.001) and non-puffy eyelids (HR = 2.47, 95% CI 1.62-3.78,  < 0.001) were independent predictors of crease retention. A significant interaction between fixation method and puffy eyelid was identified (HR = 0.34, 95% CI: 0.13-0.87,  = 0.024), indicating that the protective effect of continuous fixation was particularly pronounced in patients with puffy eyelids.

[CONCLUSION] Fixation method and eyelid puffiness were the primary determinants of crease retention, whereas surgeon experience was not an independent predictor. Continuous fixation provided superior outcomes, especially for patients with puffy eyelids. These findings suggest that, within standardized training systems, surgical technique and individualized anatomical consideration are more critical than case volume for achieving durable results in non-incisional double eyelid surgery.